US6863740B2 - Cleaning method of ceramic member - Google Patents
Cleaning method of ceramic member Download PDFInfo
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- US6863740B2 US6863740B2 US10/851,862 US85186204A US6863740B2 US 6863740 B2 US6863740 B2 US 6863740B2 US 85186204 A US85186204 A US 85186204A US 6863740 B2 US6863740 B2 US 6863740B2
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- ceramic member
- chemical liquid
- cleaning
- cleaned
- ceramic
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- 239000000919 ceramic Substances 0.000 title claims abstract description 140
- 238000004140 cleaning Methods 0.000 title claims abstract description 75
- 238000000034 method Methods 0.000 title claims abstract description 61
- 239000000126 substance Substances 0.000 claims abstract description 83
- 239000007788 liquid Substances 0.000 claims abstract description 77
- 230000002378 acidificating effect Effects 0.000 claims abstract description 38
- 238000010438 heat treatment Methods 0.000 claims abstract description 22
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 19
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 claims description 10
- 150000007524 organic acids Chemical class 0.000 claims description 4
- 239000002904 solvent Substances 0.000 claims description 4
- 239000004094 surface-active agent Substances 0.000 claims description 4
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 claims description 2
- 150000008044 alkali metal hydroxides Chemical class 0.000 claims 1
- 239000000356 contaminant Substances 0.000 abstract description 25
- 238000004519 manufacturing process Methods 0.000 description 22
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 19
- 239000004065 semiconductor Substances 0.000 description 19
- 239000000463 material Substances 0.000 description 18
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 16
- 239000007795 chemical reaction product Substances 0.000 description 16
- 229910052731 fluorine Inorganic materials 0.000 description 16
- 239000011737 fluorine Substances 0.000 description 16
- 238000005530 etching Methods 0.000 description 15
- 229910052593 corundum Inorganic materials 0.000 description 14
- 229910001845 yogo sapphire Inorganic materials 0.000 description 14
- 239000007789 gas Substances 0.000 description 13
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 description 10
- 230000000052 comparative effect Effects 0.000 description 10
- 229910052751 metal Inorganic materials 0.000 description 9
- 239000002184 metal Substances 0.000 description 9
- 229910052783 alkali metal Inorganic materials 0.000 description 7
- 150000001340 alkali metals Chemical class 0.000 description 7
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 6
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 description 6
- 239000002245 particle Substances 0.000 description 6
- 238000005229 chemical vapour deposition Methods 0.000 description 5
- 239000004973 liquid crystal related substance Substances 0.000 description 5
- 230000000007 visual effect Effects 0.000 description 5
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 4
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 4
- 239000002253 acid Substances 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 229910017604 nitric acid Inorganic materials 0.000 description 4
- -1 polyoxyethylene Polymers 0.000 description 4
- 229910052594 sapphire Inorganic materials 0.000 description 4
- 239000010980 sapphire Substances 0.000 description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- 229920003171 Poly (ethylene oxide) Polymers 0.000 description 3
- 238000004833 X-ray photoelectron spectroscopy Methods 0.000 description 3
- 150000005215 alkyl ethers Chemical class 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 229910052804 chromium Inorganic materials 0.000 description 3
- 229910003460 diamond Inorganic materials 0.000 description 3
- 239000010432 diamond Substances 0.000 description 3
- 150000002334 glycols Chemical class 0.000 description 3
- 229910052742 iron Inorganic materials 0.000 description 3
- 229910052759 nickel Inorganic materials 0.000 description 3
- 239000000758 substrate Substances 0.000 description 3
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 2
- RGHNJXZEOKUKBD-SQOUGZDYSA-N D-gluconic acid Chemical compound OC[C@@H](O)[C@@H](O)[C@H](O)[C@@H](O)C(O)=O RGHNJXZEOKUKBD-SQOUGZDYSA-N 0.000 description 2
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 description 2
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 150000001804 chlorine Chemical class 0.000 description 2
- 229910052801 chlorine Inorganic materials 0.000 description 2
- 239000000460 chlorine Substances 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 230000001627 detrimental effect Effects 0.000 description 2
- 238000011156 evaluation Methods 0.000 description 2
- 150000002221 fluorine Chemical class 0.000 description 2
- 229910052700 potassium Inorganic materials 0.000 description 2
- 239000011591 potassium Substances 0.000 description 2
- RGHNJXZEOKUKBD-UHFFFAOYSA-N D-gluconic acid Natural products OCC(O)C(O)C(O)C(O)C(O)=O RGHNJXZEOKUKBD-UHFFFAOYSA-N 0.000 description 1
- KCXVZYZYPLLWCC-UHFFFAOYSA-N EDTA Chemical compound OC(=O)CN(CC(O)=O)CCN(CC(O)=O)CC(O)=O KCXVZYZYPLLWCC-UHFFFAOYSA-N 0.000 description 1
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 description 1
- 239000005977 Ethylene Substances 0.000 description 1
- 239000006061 abrasive grain Substances 0.000 description 1
- QZPSXPBJTPJTSZ-UHFFFAOYSA-N aqua regia Chemical compound Cl.O[N+]([O-])=O QZPSXPBJTPJTSZ-UHFFFAOYSA-N 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 239000011324 bead Substances 0.000 description 1
- 229910010293 ceramic material Inorganic materials 0.000 description 1
- PMHQVHHXPFUNSP-UHFFFAOYSA-M copper(1+);methylsulfanylmethane;bromide Chemical compound Br[Cu].CSC PMHQVHHXPFUNSP-UHFFFAOYSA-M 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 238000001312 dry etching Methods 0.000 description 1
- 229960001484 edetic acid Drugs 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 239000000174 gluconic acid Substances 0.000 description 1
- 235000012208 gluconic acid Nutrition 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 1
- 239000011810 insulating material Substances 0.000 description 1
- 239000012212 insulator Substances 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 238000005342 ion exchange Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- 239000002736 nonionic surfactant Substances 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 235000005985 organic acids Nutrition 0.000 description 1
- 239000011368 organic material Substances 0.000 description 1
- 238000000053 physical method Methods 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 238000005211 surface analysis Methods 0.000 description 1
- 238000004506 ultrasonic cleaning Methods 0.000 description 1
- 238000009834 vaporization Methods 0.000 description 1
- 230000008016 vaporization Effects 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B08—CLEANING
- B08B—CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL
- B08B3/00—Cleaning by methods involving the use or presence of liquid or steam
- B08B3/04—Cleaning involving contact with liquid
- B08B3/10—Cleaning involving contact with liquid with additional treatment of the liquid or of the object being cleaned, e.g. by heat, by electricity or by vibration
- B08B3/12—Cleaning involving contact with liquid with additional treatment of the liquid or of the object being cleaned, e.g. by heat, by electricity or by vibration by sonic or ultrasonic vibrations
-
- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D7/00—Compositions of detergents based essentially on non-surface-active compounds
- C11D7/02—Inorganic compounds
- C11D7/04—Water-soluble compounds
- C11D7/06—Hydroxides
-
- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D7/00—Compositions of detergents based essentially on non-surface-active compounds
- C11D7/22—Organic compounds
- C11D7/26—Organic compounds containing oxygen
- C11D7/263—Ethers
-
- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D7/00—Compositions of detergents based essentially on non-surface-active compounds
- C11D7/22—Organic compounds
- C11D7/26—Organic compounds containing oxygen
- C11D7/265—Carboxylic acids or salts thereof
-
- C11D2111/24—
Definitions
- the alkaline chemical liquid was prepared by dissolving potassium hydroxide, citric acid, ethylene glycol and polyoxyethylene alkyl ether in pure water to have a composition shown in Table 1.
- the acidic chemical liquid containing 1.0% by weight of nitric acid and 0.2% by weight of hydrofluoric acid was used.
- the cleaning process with the alkaline chemical liquid and the cleaning process with the acidic chemical liquid were carried out in the presence of the ultrasonic wave by using the ultrasonic cleaning apparatus S8540 from Branson Ultrasonic Corporation, with the frequency of 40 kHz and the output power of 1000 W.
- the cleaning method of the ceramic member defined in the present invention permits removing with a high accuracy the contaminants from the ceramic member contaminated with the contaminants.
Abstract
Disclosed is a cleaning method of a ceramic member, which permits removing with a high accuracy the contaminants from a ceramic member contaminated with the contaminant. The cleaning method comprises the steps of processing the contaminated ceramic member with an alkaline chemical liquid having a pH value not smaller than 10 in the presence of an ultrasonic wave, processing the ceramic member processed with the alkaline chemical liquid with a prescribed acidic chemical liquid in the presence of an ultrasonic wave, and heating the ceramic member processed with the acidic chemical liquid under temperatures not lower than 1,000° C.
Description
1. Field of the Invention
The present invention relates to a cleaning method of a ceramic member.
2. Description of the Related Art
In general, a ceramic member is processed by, for example, a diamond tool in the final stage of the manufacturing process. In the process stage with the diamond tool, the debris accompanying the processing, the diamond abrasive grains, etc. (hereinafter referred to as an “extraneous material”) are attached to the surface of the ceramic member, with the result that various detrimental effects are generated during use of the ceramic member. Particularly, where the ceramic member is used in the manufacturing process of a semiconductor device or in the manufacturing process of a liquid crystal display device, it is possible for the extraneous materials to be attached to the semiconductor wafer or to the liquid crystal substrate as particles so as to give rise to defects. Such being the situation, it is necessary to completely remove in advance the extraneous materials attached to the ceramic member.
It should also be noted that it is absolutely necessary in recent years to employ the process step using a highly corrosive fluorine series or chlorine series gas or a plasma in the manufacturing process of a semiconductor device or in the manufacturing process of a liquid crystal display device. Particularly, in the manufacturing process of a semiconductor device, these corrosive gases or the plasma are frequently used in the steps of, for example, the chemical vapor deposition (CVD), the dry etching and the cleaning of the chamber. Under the circumstances, the members exposed to the corrosive gas atmosphere or to the plasma atmosphere during the process steps noted above are required to exhibit a high corrosion resistance to the corrosive gas and the plasma. In compliance with the requirement, a ceramic material such as an alumina sintered body, sapphire or an aluminum nitride sintered body is used for forming the members which are to be exposed to the corrosive gas atmosphere or to the plasma atmosphere.
However, even in the case of using such a ceramic member under the corrosive gas atmosphere or under the plasma atmosphere, a chemical reaction is generated between the ceramic member and the corrosive gas or the plasma, with the result that the surface of the ceramic member is contaminated with the reaction product. The reaction product noted above is present on the surface of the ceramic member as particles, or the particular reaction product is directly formed on the surface of the ceramic member. Since the reaction product in question renders the plasma state unstable or causes the semiconductor device, which is being manufactured, to be contaminated, it is necessary to remove the reaction product appropriately.
A chemical method is employed for removing the extraneous materials attached to the surface of the ceramic member in the manufacturing stage of the ceramic member. To be more specific, the ceramic member is cleaned with a chemical liquid for removing the extraneous materials by allowing the extraneous materials to be dissolved in the chemical liquid. On the other hand, for removing the reaction product formed by the reaction between the ceramic member and the corrosive gas or the like, which contaminates the ceramic member during the manufacturing process of the semiconductor device or the liquid crystal display device, employed is a physical method in which the reaction product in question is physically removed by polishing the surface of the ceramic member or a chemical method in which the particular reaction product is removed by allowing the reaction product to be dissolved in a chemical liquid. Japanese Patent Disclosure (Kokai) No. 2003-55070 discloses a chemical method of removing the extraneous materials and the reaction product which are hereinafter referred to as a “contaminant”. It is taught that a ceramic member contaminated with the contaminants is processed with an alkaline chemical liquid and, then, with an acidic chemical liquid, followed by applying a prescribed heat treatment to the ceramic member.
However, a rapid progress is being made in recent years in, for example, the semiconductor device in respect of the miniaturization of the circuit pattern and the degree of integration. As a result, the ceramic member, which is satisfactory when used in the manufacturing process of the conventional semiconductor device, brings about a difficulty when used in the manufacturing process of the latest semiconductor device. In other words, a difficulty is generated even in the case where the amount of the contaminants remaining on the ceramic member is lowered to reach such a low level as not to give detrimental effects to the manufactured semiconductor device when the ceramic member is used in the manufacturing process of the conventional semiconductor device. To be more specific, it is possible for the contaminants attached to the ceramic member to bring about inconveniences when the ceramic member is used in the manufacturing process of the latest semiconductor device. For example, it is possible for the yield of the manufactured latest semiconductor device to be lowered. Under the circumstances, it is of high importance to develop a cleaning method that permits removing with a higher accuracy the contaminants attached to the surface of the ceramic member so as to further decrease the residual amount of the contaminants.
An object of the present invention is to provide a cleaning method of a ceramic member that permits removing with a high accuracy the contaminants from the ceramic member.
According to the present invention, there is provided a cleaning method of a ceramic member having a contaminated surface, comprising the steps of:
-
- processing the ceramic member with an alkaline chemical liquid having a pH value not smaller than 10 in the presence of an ultrasonic wave;
- processing the ceramic member processed with the alkaline chemical liquid with a prescribed acidic chemical liquid in the presence of an ultrasonic wave; and
- heating the ceramic member processed with the acidic chemical liquid under temperatures not lower than 1,000° C.
It is desirable for the alkaline chemical liquid used in the cleaning method of the present invention for cleaning the ceramic member to contain an alkali metal, an organic acid, a glycol series solvent, a surfactant, and pure water. Also, it is desirable for the cleaning method of the present invention to further comprise the step of cleaning the ceramic member with pure water after the processing with the alkaline chemical liquid and before the processing with the acidic chemical liquid.
The cleaning method of the ceramic member according to the present invention permits removing with a high accuracy from the surface of the ceramic member the extraneous materials attached to the ceramic member during the manufacturing process of the ceramic member. The cleaning method of the present invention also permits removing the reaction product or the like formed on the surface of the ceramic member when the ceramic member is actually used under a prescribed environment in the manufacturing process of, for example, a semiconductor device. It follows that, in the case of using the ceramic member, which is subjected to the cleaning by the method of the present invention, as a prescribed member included in the manufacturing apparatus of, for example, the semiconductor device, it is possible to increase the yield and quality of the manufactured semiconductor device.
The present invention will now be described in detail. In the method of the present invention for cleaning a ceramic member, a contaminated ceramic member is processed with an alkaline chemical liquid having a pH value not smaller than 10 in the presence of an ultrasonic wave, followed by processing the ceramic member processed with the alkaline chemical liquid with an acidic chemical liquid in the presence of an ultrasonic wave. Further, the ceramic member processed with the acidic chemical liquid is heated under temperatures not lower than 1,000° C.
The material, use, etc. of the ceramic member to which the present invention is applied are not particularly limited. For example, the specific examples of the ceramic members handled in the present invention include parts of the apparatus for manufacturing a semiconductor device such as a focus ring, an electrostatic chuck, a wafer transfer hand, a chamber dome and a clamp ring, parts of the apparatus for manufacturing the liquid crystal display device such as a mask plate, as well as an insulator and true spherical beads.
The contaminated ceramic member handled in the present invention denotes the ceramic member having a extraneous material attached to the surface thereof, or the ceramic member having at least a part of the surface having a composition differing from the inherent composition of the ceramic member. To be more specific, the contaminated ceramic members handled in the present invention include, for example, a ceramic member having a cutting debris or abrasive particles attached to the surface during the manufacturing process of the ceramic member, a ceramic member having the surface chemically changed by the use of the ceramic member under a prescribed environment, for example, a corrosive environment, so as to have a reaction product formed by the reaction between the ceramic member and the corrosive environment, the reaction product being attached as particles to the surface of the ceramic member or being directly formed on the surface of the ceramic member, and a ceramic member having a particles physically attached to the surface thereof during use of the ceramic member under a prescribed environment.
The first process of cleaning the ceramic member with an alkaline chemical liquid is mainly intended to dissolve the stains of the fat and oil and organic materials attached to the surface of the ceramic member. A chemical liquid containing an alkali metal, an organic acid, a glycol series solvent, a surfactant, and pure water (ion-exchange water) is suitably used as the alkaline chemical liquid. To be more specific, potassium, which is generated by dissolving potassium hydroxide in pure water, is used as the alkali metal. The organic acids contained in the alkaline chemical liquid include, for example, citric acid, gluconic acid, and edetic acid. Ethylene glycol is suitably used as the glycol series solvent contained in the alkaline chemical liquid. Nonionic surfactant such as polyoxyethylene alkyl ether is suitably used as the surfactant. In order to enable the alkaline chemical liquid to exhibit a strong capability of dissolving, for example, the stains of fat and oil, the alkaline chemical liquid should have a pH value not smaller than 10. Also, the cleaning process with the alkaline chemical liquid is carried out in the presence of an ultrasonic wave so as to enhance the cleaning capability.
The process of cleaning the ceramic member with an acidic chemical liquid, which is carried out in the next step, is intended to remove the metal present on the surface of the ceramic member. It suffices to select appropriately the acidic chemical liquid in accordance with the kind of the metal attached to the surface of the ceramic member such that the attached metal can be effectively removed by the cleaning with the acidic chemical liquid. To be more specific, it is possible to use, for example, nitric acid, hydrofluoric acid, aqua regia, sulfuric acid, and a mixture of acetic acid and hydrofluoric acid as the acidic chemical liquid, though the acidic chemical liquid used in the present invention is not limited to the liquids exemplified above. In order to enhance the cleaning capability, the cleaning process with the acidic chemical liquid is also carried out in the presence of an ultrasonic wave.
After the cleaning process with the acidic chemical liquid, a heat treatment is applied to the ceramic member. The heat treatment is mainly intended to remove by vaporization (evaporation) or decomposition the contaminants such as the extraneous materials and the reaction product, which are left attached to the surface of the ceramic member after the processing with the acidic chemical liquid. The heat treatment is carried out by putting the ceramic member in, for example, an electric furnace, a gas furnace or a micro wave heating furnace for allowing the ceramic member to be left to stand under temperatures not lower than 1,000° C. for a prescribed time. Under temperatures lower than 1,000° C., the removal of the contaminants remaining on the surface of the ceramic member tends to be rendered insufficient.
Incidentally, the upper limit of the temperatures for the heat treatment is not particularly specified in the present invention. However, in order to prevent the ceramic member from being deformed or deteriorated during the heat treatment, the temperature for the heat treatment should be practically not higher than the sintering temperature employed in the manufacturing process of the ceramic member in the case where the ceramic member is formed of a sintered body, or should be not higher than the melting point of the ceramic member in the case where the ceramic member is formed of a single crystal body.
It is also possible to employ a plasma processing as the heat treatment. To be more specific, the contaminants attached to the ceramic member are removed by allowing a plasma to act on the ceramic member so as to heat the ceramic member. In this case, it is naturally necessary to select appropriately the atmosphere gas in order to prevent the ceramic member from being contaminated again by the plasma atmosphere.
In the cleaning method of the ceramic member specified in the present invention, the number of times of the cleaning process with an alkaline chemical liquid is not particularly limited. It is possible to carry out the cleaning process with the alkaline chemical liquid a plurality of times. In this case, it is desirable to process, for example, a contaminated ceramic member with an alkaline chemical liquid that was already used a large number of times and, then, with an alkaline chemical liquid that was already used a small number of times and, finally, with a fresh alkaline chemical liquid. This is also the case with the cleaning process with an acidic chemical liquid. It is also possible to carry out alternately the cleaning process with an alkaline chemical liquid and the cleaning process with an acidic chemical liquid. Further, it is also possible to carry out alternately the cleaning process with an alkaline chemical liquid, the cleaning process with an acidic chemical liquid, and the heat treatment.
Further, it is desirable to carry out the cleaning process of the ceramic member with pure water (water wash) after the cleaning process with the alkaline chemical liquid so as to wash away sufficiently the alkaline chemical liquid attached to the surface of the ceramic member, followed by performing the cleaning process with an acidic chemical liquid. It should be noted in this connection that, if the alkali metal component is left unremoved on the ceramic member, it is possible for the remaining alkali metal component to contaminate the environment of the manufacturing process of, for example, a semiconductor device in the case where the ceramic member is arranged in the apparatus for manufacturing the semiconductor device. Such being the situation, in order to prevent the above-noted difficulty, it is important to carry out the water wash of the ceramic member after the cleaning process with the alkaline chemical liquid for washing away the alkaline chemical liquid attached to the surface of the ceramic member. It should also be noted that, if the remaining alkaline chemical liquid is removed by the water wash noted above, it is possible to prevent the neutralization reaction from being carried out between the alkaline chemical liquid and the acidic chemical liquid. It follows that it is possible to prevent the cleaning capability of the acidic chemical liquid from being lowered and to prevent the acidic chemical liquid from being contaminated.
Further, it is also desirable to carry out the cleaning process with pure water after the cleaning process with the acidic chemical liquid. If the water wash of the ceramic member is not performed after the cleaning process with the acidic chemical liquid, it is possible for the acid component to be left unremoved on the surface of the ceramic member. In this case, the remaining acid component is evaporated during the heat treatment applied in the subsequent step and, thus, it is possible for the furnace used for the heat treatment to be contaminated with the evaporated acid component. In other words, the water wash performed after the cleaning process with the acidic chemical liquid makes it possible to prevent the furnace used for the subsequent heat treatment from being contaminated. Further, it is desirable to wash the ceramic member with pure water after the heat treatment applied to the ceramic member. Where extraneous materials derived from, for example, the heat insulating material used in the furnace are attached to the ceramic member during the heat treatment, these particles or the like can be removed from the ceramic member by the water wash.
To reiterate, extraneous materials are attached to the surface of a ceramic member during the manufacturing process of the ceramic member. Also, a reaction product is formed on the surface of the ceramic member when the ceramic member is actually used under a prescribed environment, e.g., a corrosive atmosphere. However, if the ceramic member is cleaned by the cleaning method of the present invention described above, the contaminants such as the extraneous materials and the reaction product formed on the surface of the ceramic member can be removed with a high accuracy so as to markedly decrease the residual amount of the contaminants present on the surface of the ceramic member.
Table 1 shows the plasma processing conditions, the cleaning process conditions for the cleaning process with an alkaline chemical liquid and with an acidic chemical liquid, the temperature for heating, and the results of the cleaning process, covering the case where a ceramic member formed of an alumina sintered body, i.e., Al2O3 as shown in Table 1, or a single crystal alumina, i.e., sapphire as shown in Table 1, which was processed under a plasma atmosphere, was subjected to a prescribed cleaning process. Examples 1 to 9 shown in Table 1 are directed to the cleaning process carried out within the technical scope of the present invention, and Comparative Examples 1 to 5 shown in Table 1 cover the case where the cleaning process was carried out under the conditions failing to fall within the technical scope of the present invention. Here, the alkaline chemical liquid was prepared by dissolving potassium hydroxide, citric acid, ethylene glycol and polyoxyethylene alkyl ether in pure water to have a composition shown in Table 1. The acidic chemical liquid containing 1.0% by weight of nitric acid and 0.2% by weight of hydrofluoric acid was used. The cleaning process with the alkaline chemical liquid and the cleaning process with the acidic chemical liquid were carried out in the presence of the ultrasonic wave by using the ultrasonic cleaning apparatus S8540 from Branson Ultrasonic Corporation, with the frequency of 40 kHz and the output power of 1000 W.
| TABLE 1 | ||
| Conditions for Cleaning Process of Ceramic Member | ||
| Alkaline Chemical Liquid |
| Ceramic Member | Cleaning with | Cleaning |
| Gas | Potassium | Citric | Ethylene | Polyoxyethylene | Ultrasonic | with Pure | |||||
| Material | Apparatus | Used | Hydroxide | Acid | Glycol | Alkyl Ether | pH | Wave | Water *1 | ||
| Example | 1 | Al2O3 | Etching | Fluorine | 0.7% | 0.7% | 0.7% | 1.5% | 11 | Cleaned | Cleaned |
| Apparatus | Series | ||||||||||
| 2 | Al2O3 | Etching | Fluorine | 0.5% | 0.7% | 0.7% | 1.5% | 10 | Cleaned | Cleaned | |
| Apparatus | Series | ||||||||||
| 3 | Al2O3 | CVD | Chlo- | 0.5% | 0.7% | 0.7% | 1.5% | 10 | Cleaned | Cleaned | |
| Apparatus | rine | ||||||||||
| Series | |||||||||||
| 4 | Al2O3 | CVD | Chlo- | 0.7% | 0.7% | 0.7% | 1.5% | 11 | Cleaned | Cleaned | |
| Apparatus | rine | ||||||||||
| Series | |||||||||||
| 5 | Sapphire | Etching | Fluorine | 0.5% | 0.7% | 0.7% | 1.5% | 10 | Cleaned | Cleaned | |
| Apparatus | Series | ||||||||||
| 6 | Al2O3 | Etching | Fluorine | 0.9% | 0.7% | — | 1.5% | 12 | Cleaned | Cleaned | |
| Apparatus | Series | ||||||||||
| 7 | Al2O3 | Etching | Fluorine | 0.7% | — | 0.7% | 1.5% | 11 | Cleaned | Cleaned | |
| Apparatus | Series | ||||||||||
| 8 | Al2O3 | Etching | Fluorine | 0.7% | — | — | 1.5% | 11 | Cleaned | Cleaned | |
| Apparatus | Series | ||||||||||
| 9 | Al2O3 | Etching | Fluorine | 0.5% | 0.7% | 0.7% | 1.5% | 10 | Cleaned | None | |
| Apparatus | Series | ||||||||||
| Comparative | 1 | Al2O3 | Etching | Fluorine | 0.3% | 0.7% | 0.7% | 1.5% | 9 | Cleaned | Cleaned |
| Example | Apparatus | Series | |||||||||
| 2 | Al2O3 | Etching | Fluorine | 0.5% | 0.7% | 0.7% | 1.5% | 10 | Cleaned | Cleaned | |
| Apparatus | Series | ||||||||||
| 3 | Al2O3 | Etching | Fluorine | 0.7% | 0.7% | 0.7% | 1.5% | 11 | None | Cleaned | |
| Apparatus | Series | ||||||||||
| 4 | Al2O3 | Etching | Fluorine | 0.7% | 0.7% | 0.7% | 1.5% | 11 | Cleaned | Cleaned | |
| Apparatus | Series | ||||||||||
| 5 | Al2O3 | Etching | Fluorine | 0.7% | 0.7% | 0.7% | 1.5% | 11 | Cleaned | Cleaned | |
| Apparatus | Series | ||||||||||
| Conditions for | ||
| Cleaning Process of Ceramic Member |
| Cleaning with Acidic | |||
| Chemical Liquid *2 | Result of Evaluation |
| Cleaning with | Temp. for | Removal of | Result of | ||
| Ultrasonic | Heating | Contaminants | Analysis (%) | Colored |
| Cleaning | Wave | (° C.) | *3 | F | Cl | Metal *4 | Dots | ||||
| Example | 1 | Cleaned | Cleaned | 1000 | ⊚ | 0.0 | — | 0.0 | None | ||
| 2 | Cleaned | Cleaned | 1300 | ⊚ | 0.0 | — | 0.0 | None | |||
| 3 | Cleaned | Cleaned | 1100 | ⊚ | — | 0.0 | 0.0 | None | |||
| 4 | Cleaned | Cleaned | 1300 | ⊚ | — | 0.0 | 0.0 | None | |||
| 5 | Cleaned | Cleaned | 1300 | ⊚ | 0.0 | — | 0.0 | None | |||
| 6 | Cleaned | Cleaned | 1000 | Δ | 0.0 | — | 0.0 | None | |||
| 7 | Cleaned | Cleaned | 1000 | Δ | 0.0 | — | 0.0 | None | |||
| 8 | Cleaned | Cleaned | 1300 | Δ | 0.0 | — | 0.0 | None | |||
| 9 | Cleaned | Cleaned | 1000 | ∘ | 0.0 | — | 0.0 | None | |||
| Comparative | 1 | Cleaned | Cleaned | 1000 | x | 1.0 | — | 0.0 | None | ||
| Example | 2 | Cleaned | Cleaned | 850 | x | 1.0 | — | 0.0 | None | ||
| 3 | Cleaned | Cleaned | 1000 | x | 1.0 | — | 1.0 | Found | |||
| 4 | None | None | 1000 | ⊚ | 0.0 | — | 3.0 | Found | |||
| 5 | Cleaned | None | 1000 | ⊚ | 0.0 | — | 2.0 | Found | |||
| *1 Cleaning with Pure Water after Cleaning with Alkaline Chemical Liquid | |||||||||||
| *2 Acidic Chemical Liquid contains 1.0% by weight of Nitric Acid and 0.2% by weight of Hydrofluoric Acid. | |||||||||||
| *3 Visual Observation | |||||||||||
| Complete Removal of Contaminants: ⊚, Removal of Contaminants and Slight Change in Color Tone: ∘, Removal of Contaminants and Change in Color Tone: Δ, Contaminants Left Unremoved: x | |||||||||||
| *4 Metal: Sum of Fe, Ni, Cr, Cu and Alkali Metal | |||||||||||
As shown in Table 1, the ceramic member for each of Examples 1, 2, 6 to 9 and Comparative Examples 1 to 5 was an alumina sintered body member used in an etching apparatus and exposed to a fluorine series gas plasma atmosphere for a prescribed time. Also, the ceramic member for Example 5 was a sapphire member processed under the conditions equal to those for Example 2. Further, the ceramic member for each of Examples 3 and 4 was an alumina sintered body member used in a CVD apparatus and exposed to a chlorine series gas plasma atmosphere for a prescribed time. It should be noted that the cleaning process with the acidic chemical liquid after the plasma processing was carried out by using an aqueous solution containing at least one of hydrofluoric acid, nitric acid and sulfuric acid having hydrogen peroxide added thereto, and the heat treatment after the cleaning process with the acidic chemical liquid was carried out under the air atmosphere by using an electric furnace for each of the samples for Examples 1 to 9 and Comparative Examples 1 to 5, though the conditions for the cleaning process with the acidic chemical liquid and for the heat treatment after the cleaning process with the acidic chemical liquid are not given in Table 1.
Concerning the evaluation of the ceramic member after the cleaning process, the state of removal of the contaminant from the surface of the ceramic member and the generation of colored dots were evaluated by the visual observation with an optical microscope. Also, the surface analysis for determining the amounts of fluorine, chlorine and metal components (Fe, Ni, Cr, Cu, alkali metal) was performed by the X-ray photoelectron spectroscopy (ESCA: Model 5400MC manufactured by Perkin-Elmer Corp.). Incidentally, the colored dot denotes a defect generated by traces of Fe, Ni, Cr, etc. which are left unremoved on the surface of the ceramic member.
As apparent from Table 1, the ceramic member for each of Examples 1 to 5 was found to be satisfactory in the state of removal of the contaminants, which was evaluated by the visual observation. Also, the colored dot was not recognized, and any of fluorine, chlorine and the metal component was not detected in any of the ceramic members for these Examples. The experimental data support that the state after the cleaning process was most satisfactory in the ceramic member for each of Examples 1 to 5. In each of Examples 6 to 8, the contaminant was evaluated by the visual observation as having been removed, though a change in color tone was seemingly observed on the substrate after removal of the contaminant. However, since the metal component or the like was not detected by the analysis by ESCA applied to the portion where the change in color tone was observed, it is practically possible to use again the ceramic member in the etching apparatus. In other words, the ceramic members for Examples 6 to 8 were evaluated as being practically free from problems in quality. Likewise, a portion where the color tone was seemingly changed was observed in Example 9 on the substrate after removal of the attached material, though the degree of change in the color tone was lower than that for Examples 6 to 8. In other words, the ceramic member for Example 9 was evaluated as being free from a practical problem.
On the other hand, it was found by the visual observation that the extraneous material was left unremoved on the surface of the ceramic member for each of Comparative Examples 1 to 3. In addition, the fluorine component was detected from these ceramic members. Also, the colored dot derived from the metal component remaining on the surface of the ceramic member was recognized in the ceramic member for Comparative Example 3. The extraneous material and the fluorine component were certainly removed from the ceramic members for Comparative Examples 4 and 5. However, the colored dot caused by the metal component remaining on the surface of the ceramic member was confirmed in the ceramic members for these Comparative Examples 4 and 5. Such being the situation, the ceramic members for Comparative Examples 1 to 5 were evaluated as being undesirable for re-use in the etching apparatus.
As pointed out above, it has been confirmed that the cleaning method of the ceramic member defined in the present invention permits removing with a high accuracy the contaminants from the ceramic member contaminated with the contaminants.
It should be noted that the embodiments described above are simply intended to clarify the technical idea of the present invention. Naturally, the technical scope of the present invention should not be construed solely on the basis of the specific embodiments described above. In other words, the present invention can be worked in variously modified fashions on the basis of the spirit of the present invention and within the scope defined in the accompanying claims.
Claims (2)
1. A method of cleaning a ceramic member having a contaminated surface, comprising the steps of:
cleaning the ceramic member with an alkaline chemical solution having a pH value of not less than 10 in the presence of an ultrasonic wave, said alkaline chemical solution comprising an alkali metal hydroxide, an organic acid, a glycol solvent, a surfactant and water;
cleaning the ceramic member with an acidic chemical liquid in the presence of an ultrasonic wave after the step of cleaning with said alkaline chemical solution; and
heating the ceramic member at temperatures of not less than 1,000° C. after the step of cleaning with said acidic chemical liquid.
2. The method of cleaning a ceramic member according to claim 1 , further comprising the step of cleaning the ceramic member with water after the step of cleaning the ceramic member with the alkaline chemical solution and before the step of cleaning the ceramic member with the acidic chemical liquid.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2003-143861 | 2003-05-21 | ||
| JP2003143861 | 2003-05-21 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| US20040231705A1 US20040231705A1 (en) | 2004-11-25 |
| US6863740B2 true US6863740B2 (en) | 2005-03-08 |
Family
ID=33447518
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US10/851,862 Active US6863740B2 (en) | 2003-05-21 | 2004-05-20 | Cleaning method of ceramic member |
Country Status (3)
| Country | Link |
|---|---|
| US (1) | US6863740B2 (en) |
| MY (1) | MY127376A (en) |
| SG (1) | SG135959A1 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20070144554A1 (en) * | 2005-12-23 | 2007-06-28 | Lam Research Corporation | Cleaning of electrostatic chucks using ultrasonic agitation and applied electric fields |
| CN100571841C (en) * | 2005-06-23 | 2009-12-23 | 江苏省宜兴非金属化工机械厂 | The cleaning method of microporous ceramic filter plate and device |
| US20100254043A1 (en) * | 2009-04-07 | 2010-10-07 | Alphana Technology Co., Ltd. | Method of manufacturing disk drive device for reducing adhesive amount of particles, and disk drive device manufactured by the method |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8282900B2 (en) * | 2007-02-21 | 2012-10-09 | Tosoh Corporation | Agent for rendering halogen-containing gas harmless, and method of rendering halogen-containing gas harmless using same |
| CN102513306A (en) * | 2011-12-30 | 2012-06-27 | 保定天威英利新能源有限公司 | Method for cleaning ceramic suction plates for handling solar cell slices |
| CN103878133B (en) * | 2013-10-09 | 2016-03-09 | 桐乡锦瑞化纤有限公司 | A kind of clean method of effective removal ceramic disk impurity |
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|---|---|---|---|---|
| US3033710A (en) * | 1957-03-12 | 1962-05-08 | Branson Instr | Method of surface cleaning using ultrasonic energy |
| US4713119A (en) * | 1986-03-20 | 1987-12-15 | Stauffer Chemical Company | Process for removing alkali metal aluminum silicate scale deposits from surfaces of chemical process equipment |
| US5837662A (en) * | 1997-12-12 | 1998-11-17 | Memc Electronic Materials, Inc. | Post-lapping cleaning process for silicon wafers |
| US6165279A (en) * | 1998-10-14 | 2000-12-26 | United Silicon Incorporated | Method for cleaning a semiconductor wafer |
| US6230720B1 (en) * | 1999-08-16 | 2001-05-15 | Memc Electronic Materials, Inc. | Single-operation method of cleaning semiconductors after final polishing |
| JP2003055070A (en) | 2001-08-17 | 2003-02-26 | Nihon Ceratec Co Ltd | Method for cleaning ceramic member |
| US20040045574A1 (en) * | 2000-08-11 | 2004-03-11 | Samantha Tan | System and method for cleaning semiconductor fabrication equipment parts |
| US20040060579A1 (en) * | 2002-06-24 | 2004-04-01 | Jaung-Joo Kim | Cleaning solution and method for cleaning ceramic parts using the same |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3772729B2 (en) * | 2001-11-01 | 2006-05-10 | トヨタ自動車株式会社 | Exhaust gas purification device for internal combustion engine |
-
2004
- 2004-05-20 SG SG200402815-5A patent/SG135959A1/en unknown
- 2004-05-20 US US10/851,862 patent/US6863740B2/en active Active
- 2004-05-21 MY MYPI20041951A patent/MY127376A/en unknown
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3033710A (en) * | 1957-03-12 | 1962-05-08 | Branson Instr | Method of surface cleaning using ultrasonic energy |
| US4713119A (en) * | 1986-03-20 | 1987-12-15 | Stauffer Chemical Company | Process for removing alkali metal aluminum silicate scale deposits from surfaces of chemical process equipment |
| US5837662A (en) * | 1997-12-12 | 1998-11-17 | Memc Electronic Materials, Inc. | Post-lapping cleaning process for silicon wafers |
| US6165279A (en) * | 1998-10-14 | 2000-12-26 | United Silicon Incorporated | Method for cleaning a semiconductor wafer |
| US6230720B1 (en) * | 1999-08-16 | 2001-05-15 | Memc Electronic Materials, Inc. | Single-operation method of cleaning semiconductors after final polishing |
| US20040045574A1 (en) * | 2000-08-11 | 2004-03-11 | Samantha Tan | System and method for cleaning semiconductor fabrication equipment parts |
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| US20040060579A1 (en) * | 2002-06-24 | 2004-04-01 | Jaung-Joo Kim | Cleaning solution and method for cleaning ceramic parts using the same |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100571841C (en) * | 2005-06-23 | 2009-12-23 | 江苏省宜兴非金属化工机械厂 | The cleaning method of microporous ceramic filter plate and device |
| US20070144554A1 (en) * | 2005-12-23 | 2007-06-28 | Lam Research Corporation | Cleaning of electrostatic chucks using ultrasonic agitation and applied electric fields |
| US7648582B2 (en) | 2005-12-23 | 2010-01-19 | Lam Research Corporation | Cleaning of electrostatic chucks using ultrasonic agitation and applied electric fields |
| US20100254043A1 (en) * | 2009-04-07 | 2010-10-07 | Alphana Technology Co., Ltd. | Method of manufacturing disk drive device for reducing adhesive amount of particles, and disk drive device manufactured by the method |
| US8516685B2 (en) * | 2009-04-07 | 2013-08-27 | Samsung Electro-Mechanics Japan Advanced Technology Co., Ltd. | Method of manufacturing a disk drive device for reducing adhesive amount of particles |
Also Published As
| Publication number | Publication date |
|---|---|
| MY127376A (en) | 2006-11-30 |
| SG135959A1 (en) | 2007-10-29 |
| US20040231705A1 (en) | 2004-11-25 |
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